added nonblocking support for SSL

Changelog

@@ -1,3 +1,7 @@
+2019-05-05:
+- added SSLSocket support. SSL.Connect (TCP.GetSocket())
+  it supports as well as non blocking connections with a defined timeout.
+
 2019-03-04:
 - added: TCP connections have set up a timeout of 2 seconds.
 - fixed: TCP connect set up the sock struct too fast so threaded applications had some

UDPTCPNetwork.h

@@ -113,18 +113,26 @@ private:
 	int writecnt;
 	string certfile;
 	string keyfile;
+	int timeout;
 	SSL *ssl;
 	SSL_CTX *ctx;
+	struct timeval timeout_start;
+
 	int NewServerCTX();
 	int NewClientCTX();
-	const string GetSSLErrorText(int err);
+	void TimeoutReset();
+	int TimeoutTime();
+
 public:
+	int sslerror;
+
 	SSLSocket();
 	~SSLSocket();
 
+	const string GetSSLErrorText(int err);
 	int SetCertificat(string certf, string keyf);
-	int Connect(int sockfd);
+	int Connect(int sockfd, int block_timeout);
-	int Accept(int sockfd);
+	int Accept(int sockfd, int block_timeout);
 	long int Read(char *buffer, long int len);
 	long int Write(char *buffer, long int len);
 	int Close();		// returns socket

ssl.cc

@@ -6,10 +6,12 @@
 #include <unistd.h> /* close() */
 #include <stdlib.h>
 #include <string.h> /* memset() */
-#include <sys/stat.h>
 #include <errno.h>
 #include <string.h>
 #include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/time.h>
 #include <openssl/ssl.h>
 #include <openssl/err.h>
 
@@ -22,6 +24,8 @@ SSLSocket::SSLSocket() {
 	writecnt = 0;
 	certfile = "";
 	keyfile = "";
+	sslerror = SSL_ERROR_NONE;
+	timeout = 0;
 	ctx = NULL;
 	ssl = NULL;
 	if (ssl_init == 0) {
@@ -95,33 +99,54 @@ int SSLSocket::SetCertificat(string certf, string keyf) {
 };
 
 
-int SSLSocket::Connect (int sockfd) {
+int SSLSocket::Connect (int sockfd, int block_timeout) {
+	int flags, res;
+
+	TimeoutReset();
+	sslerror = SSL_ERROR_NONE;
 	NewClientCTX();
+	timeout = block_timeout;
+
+	if (sockfd > 0 && block_timeout > 0) {
+		flags = fcntl(sockfd, F_GETFL, 0);
+		fcntl(sockfd, F_SETFL, flags | O_NONBLOCK);
+	}
 
 	ssl = SSL_new(ctx);
 	SSL_set_fd (ssl, sockfd);
-	if (SSL_connect(ssl) == -1 ) {
-		printf ("ssl connect: error\n");
-		ERR_print_errors_fp(stderr);
-		exit (1);
-	}
 
+	do {
+		res = SSL_connect(ssl);
+		if (res == -1) sslerror = SSL_get_error(ssl, -1);
+	} while (res == -1 && TimeoutTime() < timeout &&
+			(sslerror == SSL_ERROR_WANT_READ || sslerror == SSL_ERROR_WANT_WRITE));
+
+	if (res == -1) return 0;
 	return 1;
 };
 
 
 
-int SSLSocket::Accept (int sockfd) {
+int SSLSocket::Accept (int sockfd, int block_timeout) {
-	int err;
+	int flags, res;
+
+	TimeoutReset();
+	sslerror = SSL_ERROR_NONE;
+	timeout = block_timeout;
 	NewServerCTX();
 
+	if (sockfd > 0 && block_timeout > 0) {
+		flags = fcntl(sockfd, F_GETFL, 0);
+		fcntl(sockfd, F_SETFL, flags | O_NONBLOCK);
+	}
+
 	ssl = SSL_new(ctx);
 	SSL_set_fd (ssl, sockfd);
-	if (SSL_accept(ssl) == -1 ) {
+	do {
-		err = SSL_get_error(ssl, -1);
+		res = SSL_accept(ssl);
-		printf ("%s %s:%d error: %s\n", __FUNCTION__, __FILE__, __LINE__, GetSSLErrorText(err).c_str());
+		if (res == -1) sslerror = SSL_get_error(ssl, -1);
-		return 0;
+	} while (res == -1 && TimeoutTime() < timeout &&
-	}
+			(sslerror == SSL_ERROR_WANT_READ || sslerror == SSL_ERROR_WANT_WRITE));
 
 	return 1;
 };
@@ -175,6 +200,7 @@ const string SSLSocket::GetSSLErrorText(int err) {
 // close ssl and return socket.
 int SSLSocket::Close () {
 	int sock = 0;
+	int flags;
 
 	if (ssl) {
 		sock = SSL_get_fd(ssl);
@@ -187,37 +213,74 @@ int SSLSocket::Close () {
 		ctx = NULL;
 	}
 
+	if (sock > 0 && timeout > 0) {
+		flags = fcntl(sock, F_GETFL, 0);
+		fcntl(sock, F_SETFL, flags & ~(O_NONBLOCK));
+	}
+
 	return sock;
 };
 
 
 //
-// need to add timeout currently data is blocking
+//
 long int SSLSocket::Read (char *buffer, long int len) {
 	int ret;
+	sslerror = SSL_ERROR_NONE;
+
+	TimeoutReset();
 
 	if (!ssl) {
 		errno = EPROTO;
 		return -1;
 	}
 
-	ret = SSL_read(ssl, buffer, len);
+	do {
+		ret = SSL_read(ssl, buffer, len);
+		if (ret == -1) sslerror = SSL_get_error(ssl, -1);
+	} while (ret == -1 && TimeoutTime() < timeout &&
+			(sslerror == SSL_ERROR_WANT_READ || sslerror == SSL_ERROR_WANT_WRITE));
 
 	return ret;
 };
 
 
 //
-// need to add timeout currently data is blocking
+//
 long int SSLSocket::Write (char *buffer, long int len) {
 	int ret;
+	sslerror = SSL_ERROR_NONE;
+	TimeoutReset();
 
 	if (!ssl) {
 		errno = EPROTO;
 		return -1;
 	}
 
-	ret = SSL_write(ssl, buffer, len);
+	do {
+		ret = SSL_write(ssl, buffer, len);
+		if (ret == -1) sslerror = SSL_get_error(ssl, -1);
+	} while (ret == -1 && TimeoutTime() < timeout &&
+			(sslerror == SSL_ERROR_WANT_READ || sslerror == SSL_ERROR_WANT_WRITE));
 
 	return ret;
 };
+
+
+//
+// Reset Timeout Timer
+void SSLSocket::TimeoutReset() {
+	gettimeofday (&timeout_start, NULL);
+};
+
+
+//
+// Return time which has past since reset in ms.
+int SSLSocket::TimeoutTime() {
+	struct timeval tv;
+	gettimeofday (&tv, NULL);
+
+	return ((tv.tv_sec-timeout_start.tv_sec) * 1000) +
+			((tv.tv_usec-timeout_start.tv_usec) / 1000);
+};
+

test-ssl.cc

@@ -13,6 +13,8 @@ void server () {
 	SSLSocket ssl;
 	int i, timeout;
 	pid_t pid;
+	time_t time_start = time (NULL);
+	time_t time_now = time (NULL);
 	char buffer[NET_BUFFERSIZE];
 
 	//
@@ -31,7 +33,7 @@ void server () {
 
 	//
 	// check for connections
-	for (timeout = 10; timeout > 0; timeout--) {
+	for (;time_now - time_start < 10; time_now = time(NULL)) {
 		connection = tcpserver.Accept();
 		if (connection != NULL) {
 			//
@@ -47,7 +49,7 @@ void server () {
 				// returns.
 
 				tcpserver.Close();
-				if (ssl.Accept(connection->GetSocket()) != 1) {
+				if (ssl.Accept(connection->GetSocket(), 0) != 1) {
 					printf ("could not establish SSL connection:%s\n", strerror(errno));
 					exit (1);
 				}
@@ -75,7 +77,7 @@ void server () {
 				delete (connection);
 			}
 		}
-		sleep (1);
+		usleep (25000);
 	}
 };
 
@@ -83,9 +85,8 @@ void server () {
 void client () {
 	TCP tcpclient;
 	SSLSocket ssl;
-
 	char buffer[NET_BUFFERSIZE];
-	int i;
+	int i, res;
 
 	sleep (1); // wait one second to start the server
 
@@ -96,8 +97,9 @@ void client () {
 		exit (1);
 	}
 
-	if (ssl.Connect(tcpclient.GetSocket()) != 1) {
+	res = ssl.Connect(tcpclient.GetSocket(), 100);
-		printf ("could not establish SSL connection:%s\n", strerror(errno));
+	if (res == -1) {
+		printf ("could not establish SSL connection:errno:%s   sslerror:%s\n", strerror(errno), ssl.GetSSLErrorText(ssl.sslerror).c_str());
 		exit (1);
 	}
 
@@ -105,8 +107,9 @@ void client () {
 	// send some data
 	snprintf (buffer, NET_BUFFERSIZE, "nur ein kleiner Test.");
 	printf ("client:send '%s' to the server.\n", buffer);
+
 	if (ssl.Write(buffer, strlen (buffer)) != strlen (buffer)) {
-		printf ("could not send all data.\n");
+		printf ("could not send all data. errno:%s   sslerror:%s\n", strerror(errno), ssl.GetSSLErrorText(ssl.sslerror).c_str());
 		exit (1);
 	}
 

test-tcp.cc

@@ -12,6 +12,8 @@ void server () {
 	TCP *connection;
 	int i, timeout;
 	pid_t pid;
+	time_t time_start = time (NULL);
+	time_t time_now = time (NULL);
 	char buffer[NET_BUFFERSIZE];
 
 	//
@@ -23,7 +25,7 @@ void server () {
 
 	//
 	// check for connections
-	for (timeout = 5; timeout > 0; timeout--) {
+	for (;time_now - time_start < 10; time_now = time(NULL)) {
 		connection = tcpserver.Accept();
 		if (connection != NULL) {
 			//
@@ -38,7 +40,7 @@ void server () {
 				// by the parent process. Make sure the client exits and never
 				// returns.
 				tcpserver.Close();
-				i = connection->ReadTimeout(buffer, NET_BUFFERSIZE, 1000);
+				i = connection->Read(buffer, NET_BUFFERSIZE);
 				if (i > 0) {
 					int c;
 
@@ -61,7 +63,7 @@ void server () {
 				delete (connection);
 			}
 		}
-		sleep (1);
+		usleep (25000);
 	}
 };
 
@@ -80,6 +82,8 @@ void client () {
 		exit (1);
 	}
 
+	sleep (1);
+
 	//
 	// send some data
 	snprintf (buffer, NET_BUFFERSIZE, "nur ein kleiner Test.");